Work holding and feeding mechanism



Nov. 6, 1934. F, L..y GONE WORK HOLDING AND FEEDING MECHANISM OriginalFiled June 29, 1951 Patented Nov. 6, 1934 PATENT OFFICE f `1,979,366`WORK HOLDING AND FEEDING MECHANISM Frank L. ConeQWindsor, Vt. l

Original application June 29,1931, Serial No.` 547,544. Dividedand thisapplication November 1932, Serial No. 641,731

1 claim. (ci. 27a-51)] 'I'his invention relates to mechanism for holdingand feeding bar stock, as, for example, in an automatic lathe screwmachine or the like, and has for an object to provide positivework-releas- ,5 ing action not dependent on springs.

This application is a division of my application Serial No. 547,544, forMultiple spindle automatic lathe filed June 29, 1931. p

For a more complete understanding of this invention, reference may behad to the accompanying drawing in which Figure 1 is a detail sectionthrough a work spindle and related parts of a multiple spindle automaticlathe embodying this invention.

Figures 2 and 3 are similar to portions of Fgure 1 but on a largerscale.

The invention is herein illustrated as embodied in a multiple spindleautomatic lathe, though it shouldbe understood that itis not limited toany particular machine. In the machinev illustrated `a plurality of Workholders orspindles are arranged in circular series about the axis of asupporting drum which is indexed to bring the holders or spindlessuccessively into each of a plurality of positions in some of whichoperations are` performed on the work and in one or more of which theWork is fed forwardly to begin a new machine cycle after the portion ofthe Work previously operated upon has had all machining operations ofthe machine cycle performed thereon and has been cut off.

As shown in the drawing, the work holder comprises an inner stockfeeding tube having a `stock gripper 3l at its forward end outwardly ofthe drum plate 11, a collet carrying tube 32 outwardly of the stock feedtube and carrying a spring opposite direction, or to the right, the workis released. The collet is shown in Work-gripping position and the workfeeder is at the limit of its work feeding movement. Rearwardly or tothe left of the drum end the collet tube has xed thereto a sleeve 39forming an abutment for a block 40 to which are fulcrumed as at 41levers such as 42, preferably there being three such levers equallyangularly spaced about the axis of the tubes. Axially slidable on thehood tube or work spindle is a collar 45 having at one end a cam face 46which may be moved in under a relatively long arm 47 of each lever 42extending in general parallel to the axis of the tubes and by engagementwith which these lever arms are rocked outwardly to bring their innershort arms 48 into contact with a ring wear piece 49 at the end of thework spindle. This causes the block to be forced rearwardly away fromthe adjacent end of the work spindle 35, thus drawing the colletrearwardly and tightening it upon the stock 37. The collar has, however,a lost motion positive connection with the block 40, this, as shown,being formed by rods 50 positioned anguarly between the levers 42 formedas screws having their heads 51 riding in sockets 52 in the block 40 andhaving their threaded ends 53 engaged in suitable threaded sockets inthe collar 45. `A lock nut 54 on each of these screws may be used to fixthe screw in desired axial position` so that at the limit of its lostmotion, which is beyond the range of motion where the multiplying wedgeconnection from the lever arms 42 andthe cam face 46 is effective, itshead 51 actingas a` stop engages on the base of the socket 52 as thecollar"45 is moved to the right, further motion causing the block 40 tobe moved therewith and this moving the collet 32 positively to the rightwith relation to the collet hood and permitting its spring lingers` tofree themselves from the stock. The engagement of the lever arm 48 onthe member 49 carried by the spindle` also causes this motionV topositively swing the lever arms 42 inwardly against the effect ofcentrifugal force which might otherwise prevent `the freeing of thecollet. As shown the collar 45 is provided with a peripheral groove 55in which is engaged a nger 56 on a slide 57 carried on a boss 58extending rearwardly from the drum end plate 10. This block or slide 57is provided at its opposite side from the tongue 56 with a groove 60 inwhich at suitable times in the indexing motion of the drum a shoe 61 onan actuating arm 62 may be engaged as fully described in the parentapplication hereinbefcre mentioned to positively control the position ofthe collar 45.

The stock feeding tube 30 extends beyond the block 40 and has xedthereto a head 65 by which it may be actuated at suitable times as isalso fully described in the parent application. Each spindle tube 35 isjournaled for rotation in bearings and 71 in the drum plates 10 and 11and adjacent to the drum plate 11 each of these spindles has xed theretoa gear 75, all these gears meshing with a central gear 76. Thus byrotation of the gear '76 all of the work holders comprising theconcentric tubes carrying the collet hood, the collet and the work feedmay be rotated, thus to rotate the bar stock as it is presented to thetools.

From the foregoing description of an embodiment of this invention, itshould be evident to those skilled in the art that various changes andmodifications may be made without departing from the spirit or scope ofthis invention.

I claim:

In a machine of the class described, a tube, a collet hood carried byone end of saidtube, a tube slidable Within said collet hood tube andhaving a spring collet cooperating with said hood, a

block element xed to the opposite end of said collet tube, a leverfulcrumed on said block and having an arm in cooperative engagement withthe rear end of said collet hood tube and anslidable relative to theother of said elements,

stops on said rods for positively limiting a lost motion connectionbetween said collar and block to cause motion of said collar in adirection opposite to its collet gripping motion after said lost motionis taken up to free said collet from said hood to release the work, andmeans for moving said collar.

FRANK L. CONE.

